The present invention relates to a swivel lock and more particularly to a swivel lock assembly for use with a caster.
As is well known in the art, carts and other moveable equipment are commonly provided with casters and in most instances the casters located at least at one end of such equipment are capable of swiveling so as to make that end and the equipment as a whole more manueverable. It is apparent, however, that difficulties in maintaining directional control may actually reduce the units manueverability in the event that all of the casters of the cart are free to swivel since such a cart may tend to drift laterally as it is pushed or pulled. It is equally apparent that such problems may be overcome by using non-swiveling casters at the front of a push cart or at the rear of a pull cart, but these arrangements usually result in a cart which can be easily manuevered only if it is pushed or pulled from the end equipped with the swivel casters. In many instances, especially where the equipment is relatively large and heavy or where manuevering time must be reduced as much as possible (as where such casters are used on stretchers or other emergency hospital equipment), the limitations on manueverability resulting from the provision of swivel casters at only one end may present as much of a problem as the lack of directional stability resulting from the provision of swivel casters at both ends.
The prior art is exemplified by U.S. Pat. Nos. 3,070,828; 3,636,586; and 3,751,758. Co-owned U.S. Pat. Nos. 3,636,586 and 3,751,758 reveal constructions in which a locking member cooperates with the caster in order to achieve effective automatic locking against swivel action. The present invention represents an improvement upon such prior constructions in order to achieve effective automatic releasing for swivel action as well.